/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

#pragma once

#include <faiss/IndexReplicas.h>
#include <faiss/gpu/StandardGpuResources.h>
#include <functional>
#include <memory>
#include <vector>

namespace faiss {
namespace gpu {

// If we want to run multi-GPU, create a proxy to wrap the indices.
// If we don't want multi-GPU, don't involve the proxy, so it doesn't
// affect the timings.
template <typename GpuIndex>
struct IndexWrapper {
    std::vector<std::unique_ptr<faiss::gpu::StandardGpuResources>> resources;
    std::vector<std::unique_ptr<GpuIndex>> subIndex;
    std::unique_ptr<faiss::IndexReplicas> replicaIndex;

    IndexWrapper(
            int numGpus,
            std::function<std::unique_ptr<GpuIndex>(GpuResourcesProvider*, int)>
                    init);
    faiss::Index* getIndex();

    void runOnIndices(std::function<void(GpuIndex*)> f);
    void setNumProbes(size_t nprobe);
};

} // namespace gpu
} // namespace faiss

#include <faiss/gpu/perf/IndexWrapper-inl.h>
